This invention relates to electric irons and in particular, to a new and improved electric iron suitable for heat sealing of seams during laying of carpet.
Carpet sealing tape with a thermal adhesive layer is widely used in joining the edges of sections of carpet, and relatively high heat sources are ordinarily used in such electric irons. It is an object of the present invention to provide a new and improved cooling structure for an electric iron suitable for use in heat sealing of carpet, while protecting the carpet material from deforming or burning.
A variety of cooling structures for electric irons have been proposed in the past. U.S. Pat. No. 2,321,509 to Olving shows a structure with a large mass 27 of insulating material positioned between the sole plate and the housing, with an air flow path along the interior surface of the housing. A variation on this design is shown in U.S. Pat. No. 2,371,257 to Olving with an air inlet along the front and side edges and an air outlet above the housing at the rear end of the handle.
Another form of cooling arrangement is shown in U.S. Pat. No. 2,186,930 to Scharf. This design also utilizes a mass of insulation 35 over the sole plate, with an air flow path between this mass and the housing leading to a motor driven fan at the rear end of the housing. A variation on this design is shown in U.S. Pat. No. 2,373,345 to Scharf. Other motor driven fan designs are shown in U.S. Pat. Nos. 2,362,590 to Smith and 2,629,949 to Gerber et al.
U.S. Pat. No. 2,325,017 to Gough shows an iron with a fold down handle with slots along the side edges between the sole plate and top. U.S. Pat. No. 2,276,726 to Huffman shows another design with a large volume between the sole plate and housing with two narrow slots around the housing providing for air flow.
The designs of heat seaming irons presently in use do not have a means of reducing the temperature of the heatshield. Previous designs with fans proved to be too bulky. Other designs provide a plastic cover for the heatshield but it does not cover the majority of the heatshield and over time will deform. The design of the present invention provides a means of reducing the heatshield temperature without the bulk of the fan mechanism while still maintaining the basic design dimensions and criteria required by the carpet installation trade.